Mechanical kiln



Jan 6, 1931.

G. BALZ MECHANICAL KILN Filed uarch zg leza 3 Sheets- 511091. 1

Jan 6, 1931. G. BALZ MECHANICAL KILN Filed-March 29, 1928 3 Sheets-Sheet 2.v

G. BALZ MECHANICAL .KILN

Filed March 29, 1928 Fig.7

3 Sheets-Sheet 3 "Ill/1111101111174 Patented Jan. 6, 1931 TUINIITED STATES PATENTfoFFlc GEORG BALZ, or TUBINGEN, G RMANY, nssienon, {BY MESNE AssIGn ENTs, 'ro BALZ-ERZROSTUNG GESELLSCHAFT MIT BESCHRAENKTEBI-IAETUNG, or GLEIWITZ,

. GERMANY MECHANICAL Kira:

Application filed March 29, 1928, Serial No. 265,602, and. in Germany Febr11ary 22, 1927.

This invention relates to a fmechanical kiln of thekind comprising a tier of roasting chambers and provided withfagitating and ,7 propelling vanes connected to carrier arms which, in order to allow the roasting chambers to bevery low, are made of horizontal small dimensions and. supported at both ends. p

The main object ofthe' present invention is to adapt the arms to'be eifectively cooled by air, passing through the arms" and through a hollow central shaft, andthe invention consists essentially in the provision of arms each of which is formed of a plurality of tubes arranged horizontally in juxtaposition, the central shaft being composed of concentric pipes which communicate with the arm tubes I for passing air through the latter.

'Another objesct of the invention is to im- 7 accordingto the invention,

v Fig. 2, a part section of one of the carrier arm's taken in longitudinal direction,

Fig. 3, a section onthe line 3'3 of Fig. 2, Fig. .4, a part section of the arm taken 'in longitudinal direction, 7

Fig. 5, a section on the line 55 of Fig. 4:,

Fig. 6, an end elevation of one of the arm sections,

Fig. 7 ,a vertical longitudinal section of the outer end of the arm,

Fig. 8, ahorizontal' section of the same, on'the line 8- -8 of Fig. 7, r

Fig. 9, a sectional view of a carrier arm and the adjacent floors,

Fig. 10, a diagrammatic View shewing-the air circulation in the carrier arms and shaft,

and I Fig. 11, a modification of Fig. 10. p "The kiln is'composed inknown manner of a plurality of roasting chambers which are superposed on one another and on the heating source. The chambers are built up offioors 1 having an upper horizontal floor surface and a lower, arched roof for the underlying chamber, the floors being connected into an integral rigid structure. rials,.such as zinc blende or the like, are fed through a hopper 6 into thetop chamber of the kiln, and rotating agitating and propelling'vanes 18 are provided which "shift the materials gradually towards peripheral discharge apertures 2 in one chamber and towards peripheral discharge apertures in thenext. While the materials pass downwards through the kiln in this manner, the hot air rises from the heat source and flows through thechambers in the opposite directionso as to effect the roasting of the materials. The gases are discharged through a flue 23.

The vanes 18 are carried by. arms which are made of heat, gas and acid-proof metal and which are supported at both ends so that they can be of small dimensions and allow the chambers to be low. The efiiciency of the kiln will thereby be greatly enhanced, and the heat will be utilized to the utmost extent.

The carrier arms may bedriven from the circumference of the kiln'a-nd are connected to a central, hollow shaft 8. o i Thehollow shaft 8 anda pipe 33, arranged outside and concentrically with the shaft, are made in sectionswhich extend from floor to floor and which are connected by casting 33' as shewn in Figs. 2 and 3. The shaft 8 is supported at the top of the kiln by a ballbearing 8. Each carrier arm is composed of three pipes B L'arr'anged horizontally in juxtaposition and screwed into. the casting 33'.

The mate- The central pipe communicates with the shaft 8, and the outside pipescommunicate with the jacket formed'by thepipe 33 which latter is covered with :a layer of refractory material. The pipes 34: are enclosed, as best shewn in Figs. 7 and 8, in insulating sleeves which are divided into sections and supported on the pipes so as to leave intervening spaces, Sleeve'sections 37 carrying vanes 18 alternate with sleeve sections 36 serving as spacing elements. Packing rings 38 are arranged in the joints between the sleeve sections so as to render the joints tight. Capping pieces 35, through which the pipes 34 communicate with each other, terminate their arms. By this arrangement air passages are formed which 7 and returns to the pipe 33 throughthe outside pipesofthearms. The air from the first and second set of arms is 'discharged through apertures 24 into the roasting chambers. From the lower sets of arms air is discharged at the lower end of thepipe 33. In the arrangement of Fig.11 the pipe 33 is closed at the bottom as well as at the top, and the shaft 8 has a transverse partition 52 which compels the air from the third set of arinsto pass through the fourth set of arms as Well, outwards through the outer pipes 34,

and inwards into the shaft 8 through the centre pipe 34, the air being discharged at the'l ower end of the shaft 8. In the upper part of the kiln, the air circulation is the same as in Fig. 10. Where the air passesat a'considerable speed through two sets of arms in succession, a great cooling effect will be obtained. T

Thecapping pieces 35 are each formed with a flange 39 whereby the arms are connected to the carrier ring'14. This flange may also carrya toothed ring 40' adapted to mesh 7 with a driving pinion.

The arrangement ust described has the advantage, apart from the improved air circulation, that the arms can be taken topieces and their parts renewed without disturbing any of the roasting floors. For this purpose it is only necessary to remove the capping piece 35 whereupon the different tubes and sleeves can be disassembled and detached from the casing 33.

' A further development of the invention is shewn in Fig. 9. The capping piece 35 carries an annular sand channel 46 into which dips a ring 48 connected to the kiln floor next above. A similar sand channel 47, which-is bounded at the outside by a ring 49, is made in the floor nextbelow the arms Into the latter channel dipsacylindrical, sectional ring 43 carried by the capping piece 35. .A

flat sectional ring 42, arranged inside the ring 43 and connected to the latter, carries a refractory lining 44 which acts as an insulation between the kiln chamber and the atmosphere. By this arrangement therings 14 and 40 will be effectively protected from'the heat.

The shaft 8*is closed at The rings 48 and 49 can be shifted so as to provide a free passage for the capping pieces 35 and the ring sections 42, 43, when a removal of any arms is required. The ring 43 is provided with inspection apertures 45. The carrier ring 14 is supported by means of balls 41 on suitable races and may be guided by rollers 22.

I Iclaim:

1'. A mechanical kiln of the character described," comprising a tier of roasting floors, a hollow, rotatable shaft composed-of concentric pipes passing centrally through the floors, arms carried radially by the shaft in the spaces between the floors, each arm being composed of a plurality of tubes arranged in juxtaposition in a horizontalplane, the tubes of the arms and the pipes of the. shaft being in communication soasto allow air to be.

circulated through the same, insulating sleevesthreaded on the arms, agitating and propelling vanes carried by-said sleeves and means for supporting the outer ends of the arms so as to allow free movement thereof;

2. A kiln as claimed in claim 1 wherein acentral tube in each arm communicates with a central pipe of the shaft, and whei'ein outer arm tubes communicate with said central tube andwith an outer shaft pipe. I

3. A kiln as claimed in claim 1 wherein the shaft, arms and insulating sleeves are composed of detachable sections and wherein the sleeve sections are supported onthe tubes so as to form intervening spacesbetween the sleeves and tubes. 7

4. A kiln as, claimed iniclaim 1 wherein the shaft; arms and insulating sleeves are composed of detachable sections,a nd wherein the sleeve sections are supported in the tubes so as to form intervening air spaces between the sleeves and tubes, and packings interposedbetween adjacent ends of sleeve sections for tightening the joints.

5. The structure-claimed-in claim 1 and a capping piece, through which the tubes communicate with one another, terminating each armstructure. f I

6. A kiln as claimed in claim 1 wherein the shaft is formed with apertures in the upper part of the kiln structure for discharging air into the spaces-between the floors.

7. A kiln as claimed in claim 1 wherein.

thesupporting means for the outer ends of the arms consist of rings, capping piecesjterminating the outer endsof the arms, flanges on said capping pieces connecting the latter to the supporting rings, and rollers whereon the rings are supported. Y

8. A kiln as claimed in claim 1 wherein thesupporting means for the outer ends of the arms consist of rings, capping pieces terminating the outer ends of the arms, flanges on said capping pieces connecting the latter to the supporting rings, rollers whereon the rings are supported, a sand channel carried by the supporting ring of each set of arms,

' a sealing ring connected to the roasting floor above the channel so as to dip into the latter,

r a sealing ring carried by the same supporting ring so as to form a' circumferential closure for the respective roasting chamber, and a sand channel on the underlying floor co-opcrating With said latter sealing ring for sea1-, ing the chamber;

9. A kiln as claimed in claim 1 wherein the supporting means for the outer ends of the arms consist of rings, capping pieces terminating the outer ends ofthe arms, flanges on said capping pieces connecting the latter to the supporting rings, rollers Whereon the rings are supported, a sand channel carried by the supporting ring of each set of arms,

a sealing ring connected to the roasting floor above the channel so as to dip into the latter,

. a sealing ring carried by the same support ing ring so as to form a circumferential closure for the respective roasting chamber,a sand channel on the underlying fioor co-opcrating with said latter sealing ring for seal ing the chamber, and a heat insulation carried by said latter sealing ring.

10. The kiln structure claimed in claim 1 in combination with a ball bearing supporting the shaft at the top of the kiln. V

3. GEORG BALZ. 

